1. Field of the Invention
This invention relates generally to an injection pen device for injection of a drug and a drug information detection device for detecting the quantity of drug injected.
2. Description of Related Art
In the related art, an injection pen (such as an insulin injection pen) is provided for allowing a patient to select a dose and perform self-injection, such that the patient with chronic disease can perform self-treatment at home. Injection pens have significantly improved the lives of patients who must self-administer drugs. There are many different types of injection pens, including simple disposable pens or sturdy multiuse injection pens adapted to be used with pre-filled cartridges. However, regardless of their types, they are useful in assisting patients to self-administer drugs.
The patients with chronic diseases usually must be given drugs according to a predetermined schedule, so a pen-type drug delivery device is developed to provide the patient, who does not have formal medical training, to periodically perform self-injections. A common pen-type drug delivery device includes an injection dose knob and an injection unit, the injection dose knob is configured to adjust and set an injection dose, and the injection unit is configured to inject according to the injection dose set by the injection dose knob. The injection unit generally includes a piston rod configured to expel drug out of the needle for injection. The injection dose adjustment knob can be rotated to a predetermined graduation to set a stroke of the piston rod. When a user presses the injection dose knob, the injection dose knob is rotated and moved downward to push the piston rod to a predetermined location, thereby completing the injection.
Performing the injection at the correct date and time and in the right dosage is critical for managing patient illness. For example, it is very important for a diabetic to inject an adequate dose of insulin at the right time. In order to check the effect of an insulin injection, medical worker usually encourages the diabetic to record the dose and time of every injection. However, the conventional injection device is unable to record the drug dose and injection time of every injection, so the patient must record the data in a written notebook. If the patient forgets to record or records incorrect data, it may mislead the medical worker to make improper drug treatment decisions in the future.
Generally, the injection pen comprises an injection part and an adjusting part configured to determine a dose. The injection part comprises a barrel configured to contain a drug, and a plunger to inject the drug. The adjusting part comprises a sleeve and an adjusting knob, wherein the sleeve is fixed to the barrel and has graduation marks.
As discussed briefly above, the adjusting knob is rotatably connected to one end of the sleeve through a screw thread. The plunger passes through the sleeve and is connected to the adjusting knob. Before injection, the adjusting knob is rotated to drive the plunger to move upward until the adjusting knob reaches a predetermined graduation mark on the sleeve. As such, the movement of the plunger is determined, and a proper drug dose is selected. Thereafter, the adjusting knob is pushed to drive the plunger to move down, so as to push the drug out of the barrel to complete the injection.
Known injection pens can select drug dose, but critical information such as injection time, amounts of injected doses, number of injections cannot be recorded by conventional injection pens. The above information is critical to the patient for treatment and for reference to a physician. Without recording relevant information, the patient may forget the injection time and the number of injections, thereby injecting too many or too few times, to the detriment of the patient.
In the related art, the detection device mostly uses a sensor or optical recognition to detect the moving distance of the plunger, and convert a detection result into electronic data. Since a computation result is directly affected by detection of the moving distance of the plunger, the detection device requires higher accuracy for installation, needs to perform complex operations during detection, and may easily result in detection error. The detection device also cannot meet user's recording requirement.
To reduce the detection error, it would be desirable to provide a device which can accurately record critical data during the administration of the drug by using a scale board which accurately determines the number of rotations of the circuit board to record, log and transmit the critical data.
The foregoing objects and advantages of the invention are illustrative of those that can be achieved by the various exemplary embodiments and are not intended to be exhaustive or limiting of the possible advantages which can be realized. Thus, these and other objects and advantages of the various exemplary embodiments will be apparent from the description herein or can be learned from practicing the various exemplary embodiments, both as embodied herein or as modified in view of any variation that may be apparent to those skilled in the art. Accordingly, the present invention resides in the novel methods, arrangements, combinations, and improvements herein shown and described in various exemplary embodiments.